Neurotechnology

From Wikipedia
https://en.wikipedia.org/wiki/Neurotechnology

Neurotechnology encompasses any method or device in which electronics interface with the nervous system to monitor or modulate neural activity. [1] [2]

Common design goals for neurotechnologies include using neural activity readings to control external devices such as neuroprosthetics, altering neural activity via neuromodulation to repair or normalize function affected by neurological disorders, [3] or augmenting cognitive abilities. [4] In addition to their therapeutic or commercial uses, neurotechnologies also constitute powerful research tools to advance fundamental neuroscience knowledge. [5] [6] [7] [8]

Some examples of neurotechnologies include deep brain stimulation, optogenetics, transcranial magnetic stimulation and brain–computer interfaces such as cochlear implants.

Background

The field of neurotechnology has been around for nearly half a century but has only reached maturity in the last twenty years . The advent of brain imaging revolutionized the field, allowing researchers to directly monitor the brain's activities during experiments. Neurotechnology has made significant impact on society, though its presence is so commonplace that many do not realize its ubiquity. From pharmaceutical drugs to brain scanning, neurotechnology affects nearly all industrialized people either directly or indirectly, be it from drugs for depression, sleep, ADD, or anti-neurotics to cancer scanning, stroke rehabilitation, and much more.

As the field's depth increases it will potentially allow society to control and harness more of what the brain does and how it influences lifestyles and personalities. Commonplace technologies already attempt to do this; games like BrainAge, [9] and programs like Fast ForWord [10] that aim to improve brain function, are neurotechnologies.

Currently, modern science can image nearly all aspects of the brain as well as control a degree of the function of the brain. It can help control depression, over-activation, sleep deprivation, and many other conditions. Therapeutically it can help improve stroke victims' motor coordination, improve brain function, reduce epileptic episodes (see epilepsy), improve patients with degenerative motor diseases ( Parkinson's disease, Huntington's disease, ALS), and can even help alleviate phantom pain perception. [11] Advances in the field promise many new enhancements and rehabilitation methods for patients suffering from neurological problems. The neurotechnology revolution has given rise to the Decade of the Mind initiative, which was started in 2007. [12] It also offers the possibility of revealing the mechanisms by which mind and consciousness emerge from the brain.

Types

Deep brain stimulation

Deep brain stimulation is currently used in patients with movement disorders to improve the quality of life in patients. [13]

Transcranial magnetic stimulation

Transcranial magnetic stimulation (TMS) is a technique for applying magnetic fields to the brain to manipulate electrical activity at specific loci in the brain. [14] This field of study is currently receiving a large amount of attention due to the potential benefits that could come out of better understanding this technology. [15] Transcranial magnetic movement of particles in the brain shows promise for drug targeting and delivery as studies have demonstrated this to be noninvasive on brain physiology. [16]

Transcranial magnetic stimulation is a relatively new method of studying how the brain functions and is used in many research labs focused on behavioral disorders, epilepsy, PTSD, migraine, hallucinations, and other disorders. [15] Currently, repetitive transcranial magnetic stimulation is being researched to see if positive behavioral effects of TMS can be made more permanent. Some techniques combine TMS and another scanning method such as EEG to get additional information about brain activity such as cortical response. [17]

Transcranial direct current stimulation

Transcranial direct current stimulation (tDCS) is a form of neurostimulation which uses constant, low current delivered via electrodes placed on the scalp. The mechanisms underlying tDCS effects are still incompletely understood, but recent advances in neurotechnology allowing for in vivo assessment of brain electric activity during tDCS [18] promise to advance understanding of these mechanisms. Research into using tDCS on healthy adults have demonstrated that tDCS can increase cognitive performance on a variety of tasks, depending on the area of the brain being stimulated. tDCS has been used to enhance language and mathematical ability (though one form of tDCS was also found to inhibit math learning), [19] attention span, problem solving, memory, [20] and coordination.

Electrophysiology

Electroencephalography (EEG) is a method of measuring brainwave activity non-invasively. A number of electrodes are placed around the head and scalp and electrical signals are measured. [21] Clinically, EEGs are used to study epilepsy as well as stroke and tumor presence in the brain. Electrocorticography (ECoG) relies on similar principles but requires invasive implantation of electrodes on the brain's surface to measure local field potentials or action potentials more sensitively.

Magnetoencephalography (MEG) is another method of measuring activity in the brain by measuring the magnetic fields that arise from electrical currents in the brain. [22] The benefit to using MEG instead of EEG is that these fields are highly localized and give rise to better understanding of how specific loci react to stimulation or if these regions over-activate (as in epileptic seizures).

There are potential uses for EEG and MEG such as charting rehabilitation and improvement after trauma as well as testing neural conductivity in specific regions of epileptics or patients with personality disorders. EEG has been fundamental in understanding the resting brain during sleep. [21] Real-time EEG has been considered for use in lie detection. [23] Similarly, real-time fMRI is being researched as a method for pain therapy by altering how people perceive pain if they are made aware of how their brain is functioning while in pain. By providing direct and understandable feedback, researchers can help patients with chronic pain decrease their symptoms. [24]

Implants

Neurotechnological implants can be used to record and utilize brain activity to control other devices which provide feedback to the user or replace missing biological functions. [25] The most common neurodevices available for clinical use are deep brain stimulators implanted in the subthalamic nucleus for patients with Parkinson's disease. [13]

Pharmaceuticals

Pharmaceuticals play a vital role in maintaining stable brain chemistry, and are the most commonly used neurotechnology by the general public and medicine. Drugs like sertraline, methylphenidate, and zolpidem act as chemical modulators in the brain, and they allow for normal activity in many people whose brains cannot act normally under physiological conditions. While pharmaceuticals are usually not mentioned and have their own field, the role of pharmaceuticals is perhaps the most far-reaching and commonplace in modern society. Movement of magnetic particles to targeted brain regions for drug delivery is an emerging field of study and causes no detectable circuit damage. [26]

Stem cells

Stem cell technologies are always salient both in the minds of the general public and scientists because of their large potential. Recent advances in stem cell research have allowed researchers to ethically pursue studies in nearly every facet of the body, which includes the brain. Research has shown that while most of the brain does not regenerate and is typically a very difficult environment to foster regeneration, [27] there are portions of the brain with regenerative capabilities (specifically the hippocampus and the olfactory bulbs). [28] Much of the research in central nervous system regeneration is how to overcome this poor regenerative quality of the brain. It is important to note that there are therapies that improve cognition and increase the amount of neural pathways, [10] but this does not mean that there is a proliferation of neural cells in the brain. Rather, it is called a plastic rewiring of the brain (plastic because it indicates malleability) and is considered a vital part of growth. Nevertheless, many problems in patients stem from death of neurons in the brain, and researchers in the field are striving to produce technologies that enable regeneration in patients with stroke, Parkinson's diseases, severe trauma, and Alzheimer's disease, as well as many others. While still in fledgling stages of development, researchers have recently begun making very interesting progress in attempting to treat these diseases. Researchers have recently successfully produced dopaminergic neurons for transplant in patients with Parkinson's diseases with the hopes that they will be able to move again with a more steady supply of dopamine. [29][ failed verification] Many researchers are building scaffolds that could be transplanted into a patient with spinal cord trauma to present an environment that promotes growth of axons (portions of the cell attributed with transmission of electrical signals) so that patients unable to move or feel might be able to do so again. [30] The potentials are wide-ranging, but it is important to note that many of these therapies are still in the laboratory phase and are slowly being adapted in the clinic. [31] Some scientists remain skeptical with the development of the field, and warn that there is a much larger chance that electrical prosthesis will be developed to solve clinical problems such as hearing loss or paralysis before cell therapy is used in a clinic. [32][ need quotation to verify]

Ethics

Stem cells

The ethical debate about use of embryonic stem cells has stirred controversy both in the United States and abroad; although more recently these debates have lessened due to modern advances in creating induced pluripotent stem cells from adult cells. The greatest advantage for use of embryonic stem cells is the fact that they can differentiate (become) nearly any type of cell provided the right conditions and signals. However, recent advances by Shinya Yamanaka et al. have found ways to create pluripotent cells without the use of such controversial cell cultures. [33] Using the patient's own cells and re-differentiating them into the desired cell type bypasses both possible patient rejection of the embryonic stem cells and any ethical concerns associated with using them, while also providing researchers a larger supply of available cells. However, induced pluripotent cells have the potential to form benign (though potentially malignant) tumors, and tend to have poor survivability in vivo (in the living body) on damaged tissue. [34] Much of the ethics concerning use of stem cells has subsided from the embryonic/adult stem cell debate due to its rendered moot, but now societies find themselves debating whether or not this technology can be ethically used. Enhancements of traits, use of animals for tissue scaffolding, and even arguments for moral degeneration have been made with the fears that if this technology reaches its full potential a new paradigm shift will occur in human behavior.

Military application

New neurotechnologies have always garnered the appeal of governments, from lie detection technology and virtual reality to rehabilitation and understanding the psyche. Due to the Iraq War and War on Terror, American soldiers coming back from Iraq and Afghanistan are reported to have percentages up to 12% with PTSD. [35] There are many researchers hoping to improve these peoples' conditions by implementing new strategies for recovery. By combining pharmaceuticals and neurotechnologies, some researchers have discovered ways of lowering the "fear" response and theorize that it may be applicable to PTSD. [36] Virtual reality is another technology that has drawn much attention in the military. If improved, it could be possible to train soldiers how to deal with complex situations in times of peace, in order to better prepare and train a modern army.

Privacy

Finally, when these technologies are being developed society must understand that these neurotechnologies could reveal the one thing that people can always keep secret: what they are thinking. While there are large amounts of benefits associated with these technologies, it is necessary for scientists, citizens and policy makers alike to consider implications for privacy. [37] This term is important in many ethical circles concerned with the state and goals of progress in the field of neurotechnology (see Neuroethics). Current improvements such as “brain fingerprinting” or lie detection using EEG or fMRI could give rise to a set fixture of loci/emotional relationships in the brain, although these technologies are still years away from full application. [37] It is important to consider how all these neurotechnologies might affect the future of society, and it is suggested that political, scientific, and civil debates are heard about the implementation of these newer technologies that potentially offer a new wealth of once-private information. [37] Some ethicists are also concerned with the use of TMS and fear that the technique could be used to alter patients in ways that are undesired by the patient. [15]

Cognitive liberty

Cognitive liberty refers to a suggested right to self-determination of individuals to control their own mental processes, cognition, and consciousness including by the use of various neurotechnologies and psychoactive substances. This perceived right is relevant for reformation and development of associated laws.

See also

References

  1. ^ Goering S, Klein E, Specker Sullivan L, Wexler A, Agüera Y, Arcas B, et al. (April 2021). "Recommendations for Responsible Development and Application of Neurotechnologies". Neuroethics: 1–22. doi: 10.1007/s12152-021-09468-6. PMC  8081770. PMID  33942016.
  2. ^ Müller O, Rotter S (2017). "Neurotechnology: Current Developments and Ethical Issues". Frontiers in Systems Neuroscience. 11: 93. doi: 10.3389/fnsys.2017.00093. PMC  5733340. PMID  29326561.
  3. ^ Cook MJ, O'Brien TJ, Berkovic SF, Murphy M, Morokoff A, Fabinyi G, et al. (June 2013). "Prediction of seizure likelihood with a long-term, implanted seizure advisory system in patients with drug-resistant epilepsy: a first-in-man study". The Lancet. Neurology. 12 (6): 563–571. doi: 10.1016/s1474-4422(13)70075-9. PMID  23642342. S2CID  33908839.
  4. ^ Cinel C, Valeriani D, Poli R (31 January 2019). "Neurotechnologies for Human Cognitive Augmentation: Current State of the Art and Future Prospects". Frontiers in Human Neuroscience. 13: 13. doi: 10.3389/fnhum.2019.00013. PMC  6365771. PMID  30766483.
  5. ^ Wander JD, Rao RP (April 2014). "Brain-computer interfaces: a powerful tool for scientific inquiry". Current Opinion in Neurobiology. 25: 70–75. doi: 10.1016/j.conb.2013.11.013. PMC  3980496. PMID  24709603.
  6. ^ Golub MD, Chase SM, Batista AP, Yu BM (April 2016). "Brain-computer interfaces for dissecting cognitive processes underlying sensorimotor control". Current Opinion in Neurobiology. 37: 53–58. doi: 10.1016/j.conb.2015.12.005. PMC  4860084. PMID  26796293.
  7. ^ Kim CK, Adhikari A, Deisseroth K (March 2017). "Integration of optogenetics with complementary methodologies in systems neuroscience". Nature Reviews. Neuroscience. 18 (4): 222–235. doi: 10.1038/nrn.2017.15. PMC  5708544. PMID  28303019.
  8. ^ Rawji V, Latorre A, Sharma N, Rothwell JC, Rocchi L (2020-11-03). "On the Use of TMS to Investigate the Pathophysiology of Neurodegenerative Diseases". Frontiers in Neurology. 11: 584664. doi: 10.3389/fneur.2020.584664. PMC  7669623. PMID  33224098.
  9. ^ Nintendo Company of America. BrainAge (2006). Based on the work of Ryuta Kawashima, M.D.
  10. ^ a b Broman SH, Fletcher J (1999). The changing nervous system: neurobehavioral consequences of early brain disorders. Oxford University Press US. ISBN  978-0-19-512193-3.
  11. ^ Doidge N (2007). The Brain That Changes Itself: Stories of Personal Triumph from the Frontiers of Brain Science. Viking Adult. ISBN  978-0-670-03830-5.
  12. ^ Olds JL (April 2011). "For an international decade of the mind". The Malaysian Journal of Medical Sciences : MJMS. 18 (2): 1–2. PMC  3216206. PMID  22135580.
  13. ^ a b Gross RE (April 2008). "What happened to posteroventral pallidotomy for Parkinson's disease and dystonia?". Neurotherapeutics. 5 (2): 281–293. doi: 10.1016/j.nurt.2008.02.001. PMC  5084170. PMID  18394570.
  14. ^ Wassermann EM (January 1998). "Risk and safety of repetitive transcranial magnetic stimulation: report and suggested guidelines from the International Workshop on the Safety of Repetitive Transcranial Magnetic Stimulation, June 5-7, 1996". Electroencephalography and Clinical Neurophysiology. 108 (1): 1–16. doi: 10.1016/S0168-5597(97)00096-8. PMID  9474057.
  15. ^ a b c Illes J, Gallo M, Kirschen MP (2006). "An ethics perspective on transcranial magnetic stimulation (TMS) and human neuromodulation". Behavioural Neurology. 17 (3–4): 149–157. doi: 10.1155/2006/791072. PMC  5471539. PMID  17148834.
  16. ^ Ramaswamy B, Kulkarni SD, Villar PS, Smith RS, Eberly C, Araneda RC, et al. (October 2015). "Movement of magnetic nanoparticles in brain tissue: mechanisms and impact on normal neuronal function". Nanomedicine. 11 (7): 1821–1829. doi: 10.1016/j.nano.2015.06.003. PMC  4586396. PMID  26115639.
  17. ^ Veniero D, Bortoletto M, Miniussi C (July 2009). "TMS-EEG co-registration: on TMS-induced artifact". Clinical Neurophysiology. 120 (7): 1392–1399. doi: 10.1016/j.clinph.2009.04.023. hdl: 11572/145615. PMID  19535291. S2CID  4496573.
  18. ^ Soekadar SR, Witkowski M, Cossio EG, Birbaumer N, Robinson SE, Cohen LG (2013). "In vivo assessment of human brain oscillations during application of transcranial electric currents". Nature Communications. 4: 2032. Bibcode: 2013NatCo...4.2032S. doi: 10.1038/ncomms3032. PMC  4892116. PMID  23787780.
  19. ^ Grabner RH, Rütsche B, Ruff CC, Hauser TU (July 2015). "Transcranial direct current stimulation of the posterior parietal cortex modulates arithmetic learning" (PDF). The European Journal of Neuroscience. 42 (1): 1667–1674. doi: 10.1111/ejn.12947. PMID  25970697. S2CID  37724278. Lay summary. Cathodal tDCS (compared with sham) decreased learning rates during training and resulted in poorer performance which lasted over 24 h after stimulation. Anodal tDCS showed an operation-specific improvement for subtraction learning.
  20. ^ Gray SJ, Brookshire G, Casasanto D, Gallo DA (December 2015). "Electrically stimulating prefrontal cortex at retrieval improves recollection accuracy". Cortex; A Journal Devoted to the Study of the Nervous System and Behavior. 73: 188–194. doi: 10.1016/j.cortex.2015.09.003. PMID  26457823. S2CID  19886903. Lay summary. We found that stimulation of dlPFC significantly increased recollection accuracy, relative to a no-stimulation sham condition and also relative to active stimulation of a comparison region in left parietal cortex.
  21. ^ a b Purves D (2007). Neuroscience, Fourth Edition. Sinauer Associates, Inc. p. 715. ISBN  978-0-87893-697-7.
  22. ^ Hämäläinen M (November 2007). "Magnetoencephalography (MEG)". Athinoula A. Martinos Center for Biomedical Imaging.
  23. ^ Farwell LA, Smith SS (January 2001). "Using brain MERMER testing to detect knowledge despite efforts to conceal". Journal of Forensic Sciences. 46 (1): 135–143. doi: 10.1520/JFS14925J. PMID  11210899. S2CID  45516709.
  24. ^ deCharms RC, Maeda F, Glover GH, Ludlow D, Pauly JM, Soneji D, et al. (December 2005). "Control over brain activation and pain learned by using real-time functional MRI". Proceedings of the National Academy of Sciences of the United States of America. 102 (51): 18626–18631. Bibcode: 2005PNAS..10218626D. doi: 10.1073/pnas.0505210102. PMC  1311906. PMID  16352728.
  25. ^ Hochberg LR, Serruya MD, Friehs GM, Mukand JA, Saleh M, Caplan AH, et al. (July 2006). "Neuronal ensemble control of prosthetic devices by a human with tetraplegia". Nature. 442 (7099): 164–171. Bibcode: 2006Natur.442..164H. doi: 10.1038/nature04970. PMID  16838014. S2CID  4347367.
  26. ^ Ramaswamy B, Kulkarni SD, Villar PS, Smith RS, Eberly C, Araneda RC, et al. (October 2015). "Movement of magnetic nanoparticles in brain tissue: mechanisms and impact on normal neuronal function". Nanomedicine. 11 (7): 1821–1829. doi: 10.1016/j.nano.2015.06.003. PMC  4586396. PMID  26115639.
  27. ^ Sur M, Rubenstein JL (November 2005). "Patterning and plasticity of the cerebral cortex". Science. 310 (5749): 805–810. Bibcode: 2005Sci...310..805S. doi: 10.1126/science.1112070. PMID  16272112. S2CID  17225116.
  28. ^ Eriksson PS, Perfilieva E, Björk-Eriksson T, Alborn AM, Nordborg C, Peterson DA, Gage FH (November 1998). "Neurogenesis in the adult human hippocampus". Nature Medicine. 4 (11): 1313–1317. doi: 10.1038/3305. PMID  9809557.
  29. ^ Sacchetti P, Sousa KM, Hall AC, Liste I, Steffensen KR, Theofilopoulos S, et al. (October 2009). "Liver X receptors and oxysterols promote ventral midbrain neurogenesis in vivo and in human embryonic stem cells". Cell Stem Cell. 5 (4): 409–419. doi: 10.1016/j.stem.2009.08.019. PMID  19796621.
  30. ^ Sharp J, Frame J, Siegenthaler M, Nistor G, Keirstead HS (January 2010). "Human embryonic stem cell-derived oligodendrocyte progenitor cell transplants improve recovery after cervical spinal cord injury". Stem Cells. Dayton, Ohio. 28 (1): 152–63. doi: 10.1002/stem.245. PMC  3445430. PMID  19877167. Lay summaryScienceDaily.
  31. ^ Lynch Z (June 2009). "The future of neurotechnology innovation". Epilepsy & Behavior. 15 (2): 120–122. doi: 10.1016/j.yebeh.2009.03.030. PMID  19328869. S2CID  27733518.
  32. ^ Personal correspondence with Dr. Robert Gross
  33. ^ Takahashi K, Yamanaka S (August 2006). "Induction of pluripotent stem cells from mouse embryonic and adult fibroblast cultures by defined factors". Cell. 126 (4): 663–676. doi: 10.1016/j.cell.2006.07.024. hdl: 2433/159777. PMID  16904174. S2CID  1565219.
  34. ^ Laflamme MA, Chen KY, Naumova AV, Muskheli V, Fugate JA, Dupras SK, et al. (September 2007). "Cardiomyocytes derived from human embryonic stem cells in pro-survival factors enhance function of infarcted rat hearts". Nature Biotechnology. 25 (9): 1015–1024. doi: 10.1038/nbt1327. PMID  17721512. S2CID  3121694.
  35. ^ "National Center for PTSD Home". National Center for PTSD.
  36. ^ Ressler KJ, Rothbaum BO, Tannenbaum L, Anderson P, Graap K, Zimand E, et al. (November 2004). "Cognitive enhancers as adjuncts to psychotherapy: use of D-cycloserine in phobic individuals to facilitate extinction of fear". Archives of General Psychiatry. 61 (11): 1136–1144. doi: 10.1001/archpsyc.61.11.1136. PMID  15520361.
  37. ^ a b c Wolpe PR, Foster KR, Langleben DD (2005). "Emerging neurotechnologies for lie-detection: promises and perils". The American Journal of Bioethics. 5 (2): 39–49. doi: 10.1080/15265160590923367. PMID  16036700. S2CID  219640810.

Further reading